AIMS : To determine efficacy of a minimally invasive (MI) surgical approach using a human MI lumbar retractor for canine lumbosacral dorsal laminectomy and partial discectomy and to compare this
technique to the standard open surgical (OS) approach.
METHODS : Lumbosacral dorsal laminectomy and partial discectomy was performed on 16 largebreed canine cadavers using either a standard OS (n=8) or MI (n=8) approach. Skin and fascial
incision length, procedure time, and intraoperative complications were recorded. Postoperatively specimens were evaluated for laminectomy and discectomy dimensions, and visible damage to the
cauda equina and exiting nerve roots.
RESULTS : Median length of skin and fascial incisions in the OS group were longer than in the MI group (p<0.001). Median laminectomy length was similar between both approaches (p=0.234) but
width was greater for the MI than OS approach (p=0.002). Both approaches achieved similar partial
discectomy width (p=0.279). Overall surgical time was longer for MI approaches compared to OS,
with a median of 18.5 (min 15.5, max 21.8) minutes for MI compared to 14.6 (min 13.1, max 16.9)
minutes for OS (p=0.001).
CONCLUSIONS : The MI approach reduced incision lengths while retaining comparable laminectomy
and discectomy dimensions. For this in vitro model the MI approach required more time to
complete, but this difference may not be relevant in clinical cases.
CLINICAL RELEVANCE : Dogs undergoing lumbosacral dorsal laminectomy are commonly large-breed
dogs. The traditional open approach requires a large skin incision and soft tissue dissection,
especially in overweight animals. A MI approach accomplishing the same surgical result while
minimising soft tissue trauma could reduce post-operative pain and recovery time, and may lower
wound-related complications. Clinical studies are needed to confirm postoperative benefit and
assess operating times in vivo.